Background:

After lots of searching for how to install redmine on a VPS, I was able to cobble together the following instructions. This should help anyone that needs to get Redmine running on OpalStack.

References:

https://www.redmine.org/projects/redmine/wiki/redmineinstall
https://help.opalstack.com/article/125/serving-your-own-rails-project
https://help.opalstack.com/article/51/managing-databases
https://help.opalstack.com/article/73/exporting-and-importing-mariadb-databases

Instructions:

Setup project using Control Panel
1. Create a Ruby On Rails application (e.g., RAILS_APP=redmine)
2. Create a Domain to point to Redmine (e.g., SITE=redmine.myuser.opalstacked.com)
3. Create a Site to point to Redmine
4. Create a MariaDB Database (e.g., DB_NAME=redmine)
  - select UTF-8 Unicode (utf8mb4) charset
  - no need to check external access
    Note: the database name and user will be the same
    Note: a password will automatically be created for you and available on the Notices page. Either use the password on Notices page or change the MariaDB User Password (e.g., DB_USER=redmine, DB_PASSWORD=<good password>)
  - I am using MariaDB even though there are known issues, since I need to port from MySQL on WF. Postgres should work too.
Login to your server via SSH

Setup your environment

# Change these to match your setup. This just makes it easier to use the commands below
export RAILS_APP=redmine
export REDMINE_VER=4.1.1
export RAILS_APP_PATH=/home/$USER/apps/$RAILS_APP
export REDMINE_APP_PATH=$RAILS_APP_PATH/redmine-$REDMINE_VER
export GEM_HOME=$RAILS_APP_PATH/env
export PATH=$RAILS_APP_PATH/env/bin:$REDMINE_APP_PATH/bin:/usr/pgsql-11/bin/:$PATH

Install Redmine

cd $RAILS_APP_PATH
wget https://www.redmine.org/releases/redmine-$REDMINE_VER.tar.gz
tar -xvf redmine-$REDMINE_VER.tar.gz

Setup Redmine Database YML File

cd $REDMINE_APP_PATH
cp config/database.yml.example config/database.yml
vi config/database.yml

Change the database.yml file to match your setup

            production:
              adapter: mysql2
              database: <DB_NAME>
              host: localhost
              username: <DB_USER>
              password: "<DB_PASSWORD>"
              # Use "utf8" instead of "utfmb4" for MySQL prior to 5.7.7
              encoding: utf8mb4

Restore an Existing Redmine Database (Optional)

Backup existing Redmine MySQL Webfaction Database
1. Login to Webfaction
2. Navigate to Databases (https://my.webfaction.com/databases)
3. Login to phpMyAdmin (https://webXXX.webfaction.com/phpMyAdmin/, where XXX is the server number) using your database user name and password.
  Note: if you don't have the user and password name you can get them from the redmine database.yml file located on your server under: ~/webapps/redmine/redmine/config/database.yml
4. Navigate to EXPORT, leave Quick selected, select SQL from the drop dropdown and press GO
5. Your browser should download a localhost.sql file. You should rename this file to something like redmine_backup_<date>.sql
6. Use FileZilla or SCP to upload the sql backup to your new server

Restore your Redmine database into OpalStack MariaDB

Edit the backup sql file to remove the lines that create the old database
vi redmine_backup_11032020.sql

-- Database: `old_redmine_database`
--
---CREATE DATABASE IF NOT EXISTS `old_redmine_database` DEFAULT CHARACTER SET latin1 COLLATE latin1_swedish_ci;
---USE `old_redmine_database`;

Install the old database

cd $REDMINE_APP_PATH
bundle install --without development test rmagick
# import the old database - for example: mysql -p -u redmine_db redmine_user < ~/redmine_backup_11032020.sql
mysql -p -u mydbuser mydb < mydb.sql
bundle exec rake generate_secret_token
RAILS_ENV=production bundle exec rake db:migrate

Setup a New Redmine Database (Optional)

cd $REDMINE_APP_PATH
bundle install --without development test rmagick
bundle exec rake generate_secret_token
RAILS_ENV=production bundle exec rake db:migrate
RAILS_ENV=production REDMINE_LANG=en bundle exec rake redmine:load_default_data

Setup PID files

mkdir -p $REDMINE_APP_PATH/tmp/pids
cp $RAILS_APP_PATH/myproject/tmp/pids/* $REDMINE_APP_PATH/tmp/pids

Edit the development ruby file
vi $REDMINE_APP_PATH/config/environments/development.rb
add the following line right the line "config.active_support.deprecation..."

#for example config.hosts << "redmine.myuser.opalstacked.com"
config.hosts << "<SITE>"

Edit the stop script

vi $RAILS_APP_PATH/stop

change PROJECTDIR to your use the full path to the redmine install folder

#for example PROJECTDIR='/home/myuser/apps/redmine/redmine-4.1.1'
`PROJECTDIR='$HOME/apps/redmine/redmine-4.1.1' `

Edit the start script
vi ./start
change PROJECTDIR to your use the full path to the redmine install folder

#for example PROJECTDIR='/home/myuser/apps/redmine/redmine-4.1.1
PROJECTDIR='$HOME/apps/redmine/redmine-4.1.1'

change
RAILS_ENV=development
to
RAILS_ENV=production

Test the start script

cd $RAILS_APP_PATH/
./start

Test the stop script

cd $RAILS_APP_PATH/
./stop

Possible Alternatives:

Bitnami Redmine - I tried Bitnami Redmine but couldn't get the apache rules to work on my VPS. Anyhow, I think it's much better to use the above method since it utilizes the tools that OpalStack has designed for Ruby apps.

Maintenance

Opalstack automatically creates a cronjob to run your start script (above) once every 10mins. This is helpful for making sure that your redmine app restarts in case it goes down for some reason. If needed you can edit the cronjob using:
crontab -e